Question

If a(x) = 2x - 4 and b(x) = x + 2, which of the following expressions produces a quadratic function?

Answer 1

Answer:

$(ab)(x)$

Step-by-step explanation:

Data provided in the question

a(x) = 2x - 4

b(x) = x + 2

Now we go through each options

First option

$(ab)(x)=(2x-4)(x+2)$

$=2(x-2)(x+2)$

$=2(x^2-4)$

$=2x^2-8$

Second option

$\dfrac{a}{b}(x)=\dfrac{2x-4}{x+2}$

Third option

$(a-b)(x)=(2x-4)-(x+2)$

$=2x-4-x-2$

= x - 6

Fourth option

$(a+b)(x)=(2x-4)+(x+2)$

$=2x-4+x+2$

= 3x - 2

As we can see from the above options only option A is correct i.e it only produced a quadric function